I'm On Fire
by heartsmash
Summary: An arson investigation hits close to home, bringing Lindsay and Severide together to solve the crime. But when disaster strikes, how will this change their lives? Named for Bruce Springsteen's, "I'm On Fire."
1. Chapter 1

**Author's Notes**: So this idea came to me while working on "Save You." It didn't really fit into what I had planned for that story so it has begun to take on a life of it's own. I won't be updating this as frequently as "Save You" but I figured I would put this out there and see the Lindseride community thinks that this is worth continuing.

For timing, this takes place sometime in the future when Lindsay and Halstead are back together. I'm going to choose to ignore the proposed pairing of Serveride and April Saxton for the purposes of this story. The story will eventually have some mature scenes.

_Chapter One_

"We have decided not to pursue this case," Captain Lynette Cunningham stated and closed the folder that sat on her desk. "There is not enough evidence for us to focus CFD resources at this time."

Kelly Severide was astonished at the decision by the Office of Fire Investigation of the Chicago Fire Department. He stood up, slammed open the door to her office and stormed from the room, leaving Chief Boden to thank Captain Cunningham for her time and follow his hot headed squad lieutenant as they exited the central office for the fire department.

"Chief, three fires – three fucking fires in our jurisdiction in the homes of couples that are supporting multiple foster kids. And not lowlifes either! Good, salt of the Earth people who have been making a difference and they don't see a pattern?"

They went out into the tail end of another bitter Chicago winter and got into the chief's truck in order to head back to Firehouse 51.

"Severide, we can't go against the wishes of OFI. For the time being, we have to do our best to take care of anything else that seems related to these cases."

"That was a politically correct answer if I've ever heard one," Kelly grumbled.

"I don't like this any more than you do Kelly," Boden said. "This creature threatens the good that people do in the world. I don't take kindly to that and neither do you. I do have faith that OFI will act when there is enough evidence to warrant a proper investigation."

Boden pulled the car into the house and the two exited the vehicle. Severide felt defeated as they went into the kitchen area and all the eyes of the men and women of 51 looked at the two of them for information. No one liked what was going on in the neighborhood that they served. Severide took a seat at the table and let Boden deliver what he was sure was going to be an unpopular message.

"OFI has decided to not investigate the three fires that have occurred over the last three weeks in our area. There is not enough evidence for them to allocate resources at this time. As I told Lieutenant Severide on our return trip back to this house, we will do our best to combat anything related that happens and hope that OFI chooses to investigate at a later date."

Shoulders slumped at the chief's announcement and Kelly focused on reading the day's paper. But in between reading about the upcoming opening day for the White Sox and the Cubs as well as trades that the Bears were making, his mind unwillingly went back to each of the fires.

All three had been alarms in the early morning hours when members of 51 had been trying to grab some sleep in between calls. Roused from sleep, everyone had pulled on their turn out gear and traveled to the addresses called out of the intercom. The first fire they had been able to enter the building and had attempted to rescue the inhabitants, which had been to no avail. The one child that they had pulled out of the house with a pulse had expired once she got to the emergency room.

The next fires were so overcome by flames and thick, black smoke that Boden hadn't let them enter the homes out of concern for flashover. Ultimately, the chief had been right thanks to his many years of experience. The last two houses had burst into giant fireballs right in front of their eyes. Everything and everyone inside had been incinerated. They had had to call in backup to put out the flames.

The thought of those families twisted his gut. They had gone to sleep believing that they had more time only to be overcome by the thing that firefighters were supposed to be able to defeat. Severide made the decision as everyone rolled back into the house after another call that night. He knew that in order to change the minds of the brass at OFI, he would need to find his own evidence just as he and Dawson had done with the warehouse fire that had killed Shay.

"Rice, cover me for an hour," Severide told his friend and put his radio on so that he could run an errand.

It took him about ten minutes to cross town in his blue Mustang even though there was limited traffic out at that hour of night. He went to apartment 310 and knocked, waiting for the occupant to open up. Severide honestly wasn't expecting the Erin Lindsay that came to the door. Her hair was mussed, her eyes bright, lips were swollen and cheeks flushed. He had certainly interrupted something.

It had been awhile since he had seen her but the physical attraction that had once been there certainly still existed. He remembered when he made her look like that and immediately had to push that thought from his mind. They were not together any more thanks to his doing.

"Kelly, what are you doing here?" Erin asked, becoming serious.

"I know it's late but I need your help."

Detective Jay Halstead appeared behind her and sized Kelly up. Gabby had told him awhile back that the two were dating but he hadn't realized that it was still a thing. He was sure that the detective didn't appreciate his presence at Erin's door at 11 pm, no matter the reason.

"I'm going to order the Chinese, okay babe?" He kissed her on the head and disappeared into the apartment.

The flagrant act of making sure that Kelly knew his place severely pissed him off.

"Should I step back?" Kelly asked Erin, "Give him some room to pee on you and mark his territory?"

He knew it was a low blow when Erin's eyes narrowed in anger.

"Don't be an asshole Kelly. You came here needing my help remember?"

He rubbed the back of neck. He was aggravated at the situation that he was facing at 51 and even more aggravated at finding Erin in an inconvenient situation. Wasn't she the one that told him that he never needed to call?

"Listen it was a bad idea to come here this late. Can I meet you tomorrow at the district? I'm off so it's whenever you have time."

Erin cast a look over her shoulder into her apartment and Kelly figured she was debating what the man ordering Chinese food would think.

"Noon? You can buy me lunch to make up for the comment."

"Done. That going to be okay with him?"

Erin shrugged her shoulder. "He'll have to get over it."

Kelly knew that Erin was too independent to let a man control her every move, even if that man was also her partner on the force.

"Okay, noon tomorrow."

She nodded and shut the apartment door. Walking away from her door, Kelly hated the feeling that settled in his gut. It was his fault that she was now someone else's.

* * *

Kelly met her at the district and they had walked a few blocks to grab lunch. They settled on a burger joint since it wouldn't take long to get food and get her back to the office.

"So we've exchanged niceties - weather, how we've been, plans for the weekend. Now, to the reason that you were at my door last night, insulting me and asking for help."

He knew the tail end of her sentence was not meant to be a barb but instead teasing him for his offhanded comment the night before. Kelly gave her a smile before he laid the somber information on the only female detective on the Intelligence team.

"Three instances of what we believe to be arson in the homes of foster families. Fourteen kids have died and six adults."

Kelly saw the color drain from her face at the news. She had given him some insight into her past while they had been together. Although she hadn't been a foster kid by Illinois state standards, Hank Voight had turned her life around when he had taken her into his home. Her brother, Teddy, had been in the system and had suffered significantly. He knew how much Erin would care about this particular case.

"Confirmed by OFI?" she questioned when she had processed what he had told her so far.

"That's the thing. They have refrained from designating resources to investigate. They feel there is a lack of evidence."

She rolled her eyes at the decision from the arson team of the Chicago Fire Department and it wasn't for the seriousness of the situation, he would have smiled at her reaction.

"So you want Intelligence to look into it?"

"I want you to look into it, quietly. I don't want it getting back to OFI that I went around their decision."

Erin didn't even have to question why he was asking her for help. She already knew.

"Let's go speak to Hank after we're done here."

* * *

Erin breezed past Jay with Kelly in tow, headed straight for Hank's office. She knew that he would have questions but right now, she was more concerned with getting Hank's blessing on her helping out in this investigation. Erin knocked on the door frame twice inquiring if the sergeant had a minute.

Hank saw Kelly standing behind her and looked intrigued. "If representation from CFD is here, this must be good. Come in."

Erin closed the office door behind the two of them and they sat in front of Voight's desk.

"What brings you to our next of the woods, Severide?"

"Arson, sir. Or at least what my department believes to be arson. I told Erin but OFI is refusing to investigate due to insufficient evidence. Six adults and fourteen children have died in these fires. I can't let whoever is starting these fires get away with it."

"Fourteen kids? That's a lot."

"From what we've been told by the medical examiner, the three homes involved were foster families."

Voight looked to Erin. He had taken the girl in when she was 15 and problematic. She was now a phenomenal detective in his unit. Someone threatening foster families in his city was almost like they were threatening him personally. But he needed to hear from Severide what exactly CFD was looking for in this situation.

"And how can we help?"

"I'd like to look into it with assistance from the your team in order to present OFI with more evidence. I'd like them to be classified as arson and dealt with."

"And if we catch the person responsible in the midst?" Voight asked, his fingers steepled as he leaned back in his chair.

"Even better," Kelly answered without question.

Erin knew that Kelly understood that Voight had a very signature way of dealing with perpetrators of this nature. And she was pleased to hear that Kelly would look the other way if this arsonist was caught in the process of their investigation.

"Erin, you can work with Severide on this as your schedule permits. But we do have several open cases to tend to."

"Understood."

Voight turned his attention back to the squad lieutenant. "Severide, you know that foster families are something that are close to both Erin and my hearts. Let's put this asshole way."

Kelly nodded and shook the sergeant's hand. The detective and lieutenant stood up to leave the office, talking about plans to review the information that they had in their possession already.

"I'm going to send a team out the review the three crime scenes see if we can dig anything up. You around to meet tonight and start looking at whatever they come up with?"

He shoved his hands in his pockets and nodded, "Yeah, tonight's good."

"Okay, my place at 8."

Severide gave Erin's shoulder a squeeze before heading out of the bullpen and down the stairs. Erin could feel Jay's questioning gaze burning a hole into where Kelly's hand had just been. She felt like she owed him an explanation but whether it was as his partner or his girlfriend, she wasn't sure. Luckily, Hank took the decision out of her hands.

He stepped into the bullpen and called everyone to attention. "Erin's going to be working with Lieutenant Severide of 51 on a potential arson case during off hours. She's going to be focused on our open cases during shift. If she needs anything from anyone I'm sure she'll speak up, but I wanted everyone to be aware. Any questions?" When no one spoke up, he nodded. "Okay now let's get back to this crew that's using mail order brides to smuggle in smack."

The group resumed the case that had been put aside before lunch and worked well into the afternoon and evening. At 7 pm as things were just starting to wind down, Erin knew that she needed to start heading out the door to meet Severide at her apartment. As she packed up the arson case files that the scene investigators had given her on the crime scenes, Jay approached her desk.

"So what do you want to do tonight? Thai? Indian?"

"I can't tonight. I'm meeting with Kelly to start a review on the crime scenes."

Erin looked into his green eyes and immediately knew that he was not happy with the situation. She didn't think that he would be considering that she and Kelly had dated.

"Do you want another set of hands or eyes?" he asked.

"I think we'll stick with just the two for now." The hurt look that appeared on his face made her regret her answer. "I'll see you in the morning okay? I'll bring you a coffee."

He nodded solemnly and she stretched up to kiss him. Her mind wandered to thinking about how different Jay and Kelly kissed, which she immediately had to bury.

"Love you," she told him as she backed out of the bullpen and headed out to her apartment.

It didn't shock her that Kelly arrived early or that he came ready to feed her. He held a giant plastic bag filled to the brim.

"Thai Lagoon?" she asked as she sniffed the air. The scent of the fragrant Asian cuisine wafted out of the bag and caught her attention.

"I know you work better on a full stomach."

"What's that supposed to mean?"

"You get a little cranky when you're hungry. I figured I'd prevent that from happening."

She scowled at his keen observation of her and led him inside. He unpacked the bag as she got two beers out of the fridge. Erin smiled when she saw that he had gotten her favorite - Thai spring rolls and beef Pad Thai.

"You remembered?" she asked taking a swig of her beer.

"Hard to forget. You ordered it every time we went there."

She bit her tongue from reminding him that they had dated months and months ago. Ultimately it was sweet that he had remembered her food preference. She took the beers over to the table where she had the case files that the forensics teams had prepared for her as well as the information that Kelly had given her from the jump. Kelly brought the food over and listened to what she had to say.

"Forensics found evidence of an accelerant in each of the three fires. They haven't been able to identify the substance yet but they're working on it. If its something purchased maybe we can nail down who's been buying these items in such large quantities."

"Casey said the flames looked almost yellow when truck got there so most likely we're looking at gasoline being the accelerant. But we're going to need to have something else to go along with that – evidence of matches or homemade timing device."

Erin poured over the files and dragging her finger along the information that had ben prepared as Kelly looked over the crime scene photos.

"Oh," she said and that piqued his interest.

"What?"

"The team found a sizable hole in each of the roofs at the crime scenes."

Kelly grit his teeth at the information. "Bastard wanted the fires to have enough oxygen." Erin gave him a quizzical look.

"Any arson investigation will classify arson based on the fire triangle – oxygen, fuel source and heat. Putting a hole in the roof would allow the fire to climb through the house quickly and wouldn't be something the residents would realize. Did the team figure out how the person got in to the houses?"

"Basements - two windows and sub-ground door."

"He set it up perfectly. The accelerant in the basement so that the fire would take on a life of its own, we had no shot."

Erin could feel the anger radiating off Kelly and knew that she needed to calm him down before he flew off the handle. She was angry too but she knew that Kelly took this personally seeing as how he was a firefighter and he had been unable to combat the fires that had claimed so many lives recently.

She gently laid a hand on top of one of his clenched fists, hoping that the touch would ease some of his fury that he felt. The touch was electric. He looked up at her and she knew that he felt it too.

Clearing her throat, Erin removed her hand from his and reassured him with words.

"We're going to catch this guy. I can feel it. He owes us a mistake."


	2. Chapter 2

**Author's Notes**: Took a break between Save You updates to get out this chapter of I'm On Fire. I'm glad that the reception for this has been positive thus far. I'm pretty sure that you won't see what is coming down the line (my very effed up mind at work) but I'm excited to continue this after another two or three Save You chapters.

Erin is wearing the To Love Again gown by Badgley Mischka, which is easily found via Google if you want a visual while reading.

_Chapter Two_

It had been a busy day for Firehouse 51. Three car accidents, a fire at a local restaurant and another house fire had kept everyone on their toes during shift. Everyone tried to get some rest as they barreled towards midnight when the wail of the alarm went off.

_Truck 81…Squad 3…Ambulance 61…Battalion 25…__2947 W Logan Blv__d, __house fire. _

In his gut, Kelly knew that this was once again the work of their arsonist. It fit the pattern of the past three fires. A late at night house fire that needed all hands on deck. After he got suited up and jumped into the passenger seat of the squad truck, he pulled out his phone and sent Erin a message so that she was aware it was happening again.

After the rest of the squad was ready to go and in the truck, they flipped on their sirens and rolled out of the firehouse on the way to the address given by dispatch. When they turned onto Logan Boulevard, he was not expecting to see Erin there alongside Voight and Halstead. There wasn't much that the sergeant and two detectives could do except control the scene and the one hysterical person that was outside the house. Kelly assumed that he was the one that had called in the fire.

"You have save my daughter! My daughter is inside!" the man yelled as they started to exit their trucks and grab their gear.

Erin intervened and tried to calm the man down, explaining that the fire department was going to do everything that they could.

"Who's in the house sir? Just your daughter?" Boden asked the man.

"Our au pair, Ingrid, lives with us. She takes care of Korinne after school while I'm at work. God damnit, I shouldn't have gone to that company dinner tonight."

Kelly heard that they were looking for two victims and led the charge with the rest of squad into the house before the flames could get any worse. He knew that Boden was watching how the fire acted to let them know how much time they had inside.

The fire was cruel but not as bad as the second and third fires. They actually had a shot at rescuing this man's daughter and live in nanny. Navigating through the smoke and flames, each member repeated the call out for victims.

"Fire department! Call out!"

The noise was so small that Kelly wasn't sure that he had actually heard it at first but once he heard Rice say the phrase again, he could hear someone respond. But the smoke was thick and even if there were someone close to them, Kelly wouldn't have been able to make them out.

"Casey, where's the thermal imaging camera?"

He heard the truck lieutenant call to Dawson for the device and she bought it up to the squad lieutenant so that the search for Korinne and Ingrid could continue. The device read the scene and behind the couch, the heat of a small body came onto the screen. Kelly went to the spot and found the little girl whimpering. Her dark skin was tinged with soot and her left side was already burned, almost as if she had pulled herself away from the flames that were overtaking the room.

"Come on darling, let's get you out of here," Severide said and lifted the little girl into his arms with ease. He tried to be gentle as he removed her from the house, feeling horrible for putting any pressure on her wounds.

The man ran to Severide as he carried Korinne out onto the street where Brett and Mills met him with the stretcher. He placed the little girl onto it and let the two paramedics perform their duties. Lifting his mask off, he went over by the chief to see if the others had found the other victim yet.

"Everyone you've got three minutes left in that house before I'm calling it," Boden said into the radio as he watched the flames that were now shooting out of the second floor windows, causing even more thick smoke to curl into the sky.

It took about another minute of silence before Otis' voice cut through stating that they had found Ingrid. The crew from truck exited the house, the au pair being carried out by Otis and Hermann. The look on their faces said that she was already gone.

The rage bubbled up inside Kelly. Not even the sirens of the ambulance telling him that Korinne was on her way to hospital and still had a fighting chance was enough to quell the anger. Taking off his helmet, he flung it to the ground.

"Take a walk Kelly," Boden boomed, his tone gruff. Kelly expected nothing less of his chief at this moment. It had been another difficult fire and another puzzle piece added to the arsonist issue. This was not easy on anyone at 51.

So in that moment he listened, heading away from the scene down the darkened street that was lit up every few seconds by the lights of the fire trucks and cop cars. He heard boots behind him and he didn't have to turn around to know that it was Erin, following him, concerned for his well-being. He stopped at the corner leaning heavily against the street sign. Erin came to stand in front of him, her arms crossed, a black beanie covering her head from the cold and her sharp hazel eyes taking him in.

"You okay?" she questioned.

"The exact opposite actually."

"You got her out in time. She's got a shot."

"True, but this asshole continues to be three steps ahead. I want to be on offense for once, not defense."

Erin nodded her understanding. Despite the time they dedicated to the case over the past two weeks, they weren't much further at catching him.

"The fire was different Kelly. One kid and an au pair? Maybe it'll be what we need to get on offense."

He swallowed the lump in his throat, thinking about the little girl on the way to the hospital. She was only nine. She had her whole life ahead of her and some dickweed had attempted to take that away from her. Erin wrapped her arms around him and it calmed him considerably. It was her patented way of making him feel better just as she had so many times before. He was taken with how she stilled smelled just as he remembered.

"Thanks," he said, sincerely meaning it. She was the one person who wasn't scared to approach him when he was angry and he was thankful to have a partner in this.

"Let's head back," she encouraged as she let him out of her embrace.

"Yeah, fine."

Erin walked him back to the squad truck before sliding into the passenger seat of Voight's SUV. Despite the situation, Kelly knew that having Erin back around was the best thing that could come out of these fires.

* * *

Sleeping forever had sounded like the best solution after the crappy end of shift but the person on the other side of his apartment door had other thoughts in mind. The knocking had started twenty minutes ago and they continued to knock, not taking a hint that he didn't want to answer. Eventually, he gave up and meandered to the door as he pulled on a pair sweatpants over his boxers. Seeing Erin on the other side with an offering of coffee was better than what he had been expecting, namely Boden chewing his ass out for his behavior the night before.

"Can I come in?" she asked and he moved to the side to allow her entrance to his apartment.

She appraised the one bedroom that he had moved into recently. After spending a good amount of time living in the guest bedroom of Casey and Dawson's pre-wedding apartment, he knew that it was time to go when they had finally found a brownstone that they loved and the wedding date was rapidly approaching. Living on his own wasn't awful – it was a bit lonely seeing as he had always had a roommate but he made it work.

"What's up?" he asked taking the coffee to his kitchen to warm up.

"That was hot when I started knocking minutes ago," she commented, watching him.

"Maybe you should have broken down the door."

"I was toying with the idea but then I would have had to call Atwater for the battering ram and it just would have become this whole big thing."

He smiled at her obvious teasing and he noted that she was smiling too, her dimples on full display. It felt wrong considering Korinne was in the burn unit at Chicago Med. She was still critical but the doctors were optimistic for a full recovery.

"I came to check on you. Last night was tough. I know how bad we need the upper hand and I already have a team at the house scouring top to bottom for clues."

No one could ever accuse Erin Lindsay of being a lazy cop. She was exactly the opposite. She was one of the best that he knew, always out to keep Chicago safe and fight for the victims.

"I'm okay but you know how I feel already."

She nodded and Kelly knew that she understood. There had been too much destruction and it was up to them to end it. The question was when were they going to catch a break in the case.

"What's that out for?" she asked noting a tux hung on the coat rack.

Kelly groaned. He almost forgot about the black tie benefit that night and Erin had done a great job of reminding him. He had picked up the rented tux before yesterday's shift and the event hadn't crossed his mind since.

"There's a thing tonight to raise money for CFD and Casey is being honored for heroism for that hoarder fire from a few months back. It's a big thing. The mayor is going."

It was a mandatory event for the house as there were about eight tables purchased to accommodate members of all the different shifts to support Casey.

"Swanky. Could be a good time."

As a lieutenant he was invited with a guest but he had no one to bring until he opened his big mouth. "You want to come with?"

It shocked him when she immediately agreed and he was sure that the surprise read on his face.

"I shouldn't have asked. I think your boyfriend is going to have a problem with you with me."

He knew that he should have kept his trap shut with how she reacted to his secondary statement. Erin put her hands on her hips and narrowed her eyes.

"Are we not friends? Because I thought we were."

"I know that but I'm concerned what he thinks. I don't want to cause any problems."

He truthfully didn't want to cause problems between her and Halstead. From what Gabby had told him, they had already broken up once before because of Voight's disapproval.

"Kelly, I'm an independent person. The person I'm with needs to support that. Pick me up at 6:30."

With that she left his apartment. All Kelly knew was that he suddenly he had a date for that night's event and he was in desperate need of a clean shave.

* * *

Erin knew that it was going to be a fight the minute that she responded to Jay's text and told him that she wasn't free for a movie that night. When Kelly's name came into the discussion, he all but demanded that she come over to his apartment to explain. Erin agreed if only because she didn't see this to be the big deal that he was making it out to be.

She didn't know if he had heard her on the stairs up to his apartment but he was waiting with his apartment door open, arms crossed and looking furious.

"Erin you cannot be serious. You're going to a benefit dinner with him when you could be going to a movie with me, the person you're dating."

Erin knew that this was a mistrust centered in on the fact that she and Kelly had dated. If it had been Justin or just a friend, this would not be the situation that it was. She moved into the apartment and let him close the door. They didn't need all his neighbors knowing their business.

"Jay, he's my friend. If Megan wanted you to come to a dinner in recognition of shooting victims, I wouldn't think twice about it."

"Don't bring Megan into this. I never slept with her," Jay told her emphatically. "It's a fucking date Erin. You're going to a black tie event on his arm and I'm your boyfriend. Not him."

Erin had had enough of this conversation. She didn't feel like she needed to defend herself to anyone particularly to someone that claimed he loved her. It was her turn to cross her arms.

"You really want to push that fact that you're my boyfriend? Because if you keep this attitude up, you won't be much longer."

Jay looked like she had kicked him in the gut but she felt strongly about this. Jay closed his eyes and pinched the bridge of his nose before heaving a sigh.

"I don't want to fight with you. I just hate that our free time is turning into you spending time with him for the sake of this case."

She moved toward him and cupped his cheek gently, looking into his green eyes.

"You saw that little girl Jay. She's nine. And she is going to have a really hard road in front of her because some prick felt the need to set her house on fire. I need to figure out who this guy is, why he's targeting these people and take him down. Keeping Kelly sane during this investigation is just as important as cracking the case."

He kissed her palm and pulled her towards him. She wound her arms around his neck. He had been right in one sense. They had not had a lot of free time together and it was starting to take its toll.

"How can I help Erin? Seriously."

Jay was a good cop. He had the same approach as she did most of the time and she knew that his attention to detail from years in the military might come in handy.

"Kelly and I have been over the files at least three times. Can you look at them and see if there's something that we're missing?"

"Of course," he replied. "Anything else?"

"Well, I need some help picking out a dress for tonight. Do you think you could help me with that?" Erin asked him, her right hand drifting down his chest towards his belt.

Jay's eyes lit up at the suggestion in her words.

"I believe I can," he responded with a light laugh.

* * *

Kelly pulled his blue Mustang to the curb in front of Erin's apartment building. It was cold out so he wished he had an overcoat to go over his tuxedo but it had been a last minute thought that he couldn't take care of before needing to pick up Erin. Getting out of the car, he rubbed his hands together and blow into them to combat the chill. He started in the direction of the building only to see her come down the steps. She had obviously seen him pull up.

The sight of her stopped him in his tracks. Her hair was down in her signature waves but she had accentuated her eyes with smoky shadow and her lips were painted red to match the dress that she wore. The woman made the dress look stunning, not the other way around. It was long and bright red, flowing around her feet as she walked to reveal a slit at the front. A black shawl was pulled tight around shoulders to stop the Chicago winter wind.

"Wow," he stated and she ducked her head at the compliment.

"You're not so bad yourself," Erin responded and walked to the car. He opened the passenger door and slid inside. He went around to the driver's side, glad for a minute to collect his thoughts. In his heart of hearts, Kelly knew that he didn't want to cause any trouble for Erin and Halstead but she was making it incredibly hard for him to only want to be friends.

He drove them over to the InterContinental Chicago on Michigan Avenue and handed off his car to the valet before offering Erin his arm to head inside. The ballroom was decorated in shades of cream and gold with more tables than he could possibly count. There was a good crowd already there, including plenty of security due to the Mayor Emmanuel's presence at the event. The band was just getting settled and he was sure that soon they would have plenty of people on the floor.

"Jeez," Erin said looking all over with wide eyes. "I stand by statement from this morning."

"Swanky?" Kelly questioned and she nodded with a smile.

The two moved further into the ballroom and Kelly saw Casey and the future Mrs. Casey at standing next to the chief and his wife, Donna. Gabby smiled when she saw Erin and gave her a hug.

"Donna, this is Erin Lindsay. She's a detective with the Intelligence team for the Chicago Police Department," Gabby introduced

Donna shook her hand before asking "You and Kelly are dating?"

Kelly should have suspected that this would have been an assumption by someone that had never met Erin and saw the two of them together at this event.

"Just friends," Erin told the chief's wife politely.

"That's a shame. The two of you look outstanding together."

Kelly gave Donna a kiss on the cheek and shook the chief's hand before he led Erin to the bar.

"Sorry about that," he apologized as they got to the makeshift bar and he ordered them two Old Fashioneds.

"It's fine," Erin told him and he knew that she was sincere. "Donna could have said worse things."

Kelly handed her a glass and dropped a dollar in the bartender's tip jar before they walked away. He saw the blonde curled head walked towards them dressed in a black gown and he resisted the urge to groan and instead tensed up. He knew Erin felt that immediately and she waited for him to explain.

"That's Lynette Cunningham. She's a captain in the Office of Fire Investigation. She was the one to tell me that they weren't investigating the fires."

Erin didn't hesitate after hearing that, heading straight towards the woman. Kelly approached the situation slowly, interested to see how this was going to play out.

"Captain Cunningham?" Erin questioned and held out her hand to greet her. "Detective Erin Lindsay, Intelligence."

"I'm glad you could come and support us. We always need to support each other in these dangerous occupations."

"Yeah, no," Erin stated and Kelly could immediately see that Cunningham was caught off guard. "You know Lieutenant Severide? He's brought my team and I in on the case that you closed the book on a few weeks ago. I'm not sure why you felt that it was not worth investigating because I have a real problem with that."

"It had a lack of evidence…"

Erin quickly cut her off. "Oh, trust me there's plenty of evidence now that a little focus has been put on it. Intelligence is going to solve this case along with Lieutenant Severide's help. And then I'm going to have my sergeant make the Fire Commissioner aware of the unwillingness to look into matters that have a clear pattern, evidence or not."

Captain Cunningham's mouth hung open at her words. Erin grabbed Kelly by the hand and pulled him away. He couldn't help but lean over and whisper in her ear.

"You're amazing."

He duly noted the giant smile on her face at his words.


	3. Chapter 3

Author's Notes: It's been hard to finish this chapter since this past week's crossover as I know that Nadia's death is obviously traumatic for Erin. There will be plenty of it mentioned in Save You when I get to that portion of the season.

But here is the next chapter of I'm On Fire and there is finally a break in the case. As well as some sexual tension that you can cut with a knife! Let me know your thoughts and look for an update of Save You next.

_Chapter Three_

No one could ever accuse Matt Casey of being anything but charismatic behind the microphone. He had just been granted the heroism award by Mayor Emmanuel and Matt now addressed the crowd that had gathered at the InterContinental Chicago.

"No one becomes a firefighter to be a hero. We do it to help others. We are born with the innate need to be on the front lines of our neighborhoods to protect the people who live there," he said. "The same can be said for our brothers and sisters in blue." Matt winked at Erin and she shook her head slightly, a grin on her lips.

"I am so grateful to be honored with this award but I would not be up here nor would I survive most shifts without my family at Firehouse 51. The fire that I am being honored for was not an easy one to combat. There were a few moments where I even believed that I may have lost my beautiful fiancée, Gabriella."

Matt took a beat, choked up by memories of the blaze that they had overcome despite it spreading into the house next door. By department standards, they had done a remarkable job.

"Thankfully, that was not the case. My family worked together to put out the fire and returned to 51. I feel though that I share this award with every firefighter out there because everyone deserves to feel honored for this job that we do. Thank you."

The crowd burst into applause and many of them launched to their feet, which resulted in the entire room giving him a standing ovation.

"He's been working on that speech for week. I'm glad it's over," Gabby told Erin, taking a sip of champagne. It was obvious that she had been incredibly nervous for him.

"He did great. Such a great speaker," Erin told the firefighter, who was giving her fiancé a big smile as he returned to the table, his award in hand.

"Atta boy," Kelly greeted and clapped him on the back in congratulations. "Celebratory cigars?"

The two gentlemen did not have a chance to leave as the fire commissioner of the entire Chicago Fire Department approached their table, his face pinched with what looked like a mixture of anger and concern.

"Who, may I ask, is Detective Lindsay?" he questioned and Erin stood without a second thought. "Come with me please."

Erin followed the commissioner to a corner of the ballroom, Kelly flanking her side without question. She suddenly wished that she had listened to Kelly and hadn't approached Cunningham about the investigation. But the self-righteous way that the woman seemed to float through life, as if she did broke her back at her job each day now resulted in her speaking with the fire commissioner.

"I take it that you had some words with Captain Cunningham earlier."

'What a narc,' Erin thought sourly before squaring her shoulders in resolution. "I did Commissioner. May I ask what is your involvement in a disagreement between two women?"

Truthfully, she was downplaying the verbal smackdown that she had delivered to the lank arson officer.

"When that disagreement stems from a series of fires that I am now just being brought in on. I'm not speaking with you to castigate you, the exact opposite. I'm thankful to have you and your team looking into this. You too, Lieutenant Severide." The commissioner held out his hand for Erin to shake and she did so before he also shook Kelly's hand. "You contact me if you need any sort of assistance with this matter. Lieutenant, maybe after this investigation is over you will consider bringing your talents to OFI. I could use you on the team, seeing as there appears to be some weak links exposing themselves."

He wished them both a good evening before heading back to his VIP table. After the older gentleman was out of view, Erin let out the nervous breath that she didn't realize she had been holding. She definitely perceived his pulling them to the side as a bad sign. She had never been thanked for being a pit bull before.

"Goddamn, I really thought we were going to get our asses chewed out there."

"You and me both," Erin responded, "I guess Cunningham is on the Ivory Tower shit list by her own hand."

"Can't say I'm broken up about that one," he told her with a smirk. Erin smiled back.

They went back to the table and quelled the anxious looks from the members of 51.

"Relax everyone, all's good," she told them which allowed everyone to let out a collective sigh of relief. "Now let's dance," she said and grabbed Otis to pull him on the dance floor.

The party went on for a several more hours before Erin finally limped back to the table, her heels now more of a torture device than complimentary to her outfit. She took a seat at the table and removed the shoes. She moaned at the feeling of her feet being free, crossing one leg over her knee to massage the appendage. Looking up, she caught Kelly staring at her with a look of mild amusement on his face.

"I'd like to see you wear these things," Erin grumbled and turned her attention to the other foot.

"No thank you," he quickly responded and took a seat next to her at the table.

Erin watched as the chief spun his wife to the music and Casey held Gabby close as the band played on. The sight made her smile. For one night, everyone from the firehouse was able to forget the recent string of fires and focus on their loved ones.

"Think you could slip those things on for one more dance?" he asked, standing up and holding out his hand to her. She nodded and slid her shoes back on before she stood and put her hand in his, allowing him to guide her onto the dance floor. The band transitioned into an old Dean Martin classic.

They had spent most of the even dancing in a large group, so Erin kept telling herself that it was only one slow dance and it meant nothing. They were friends, enjoying one of the last songs of the night. But as Kelly's right hand found purchase on the small of her back and his left gently grasped her right hand in his, her theory began to lose its footing.

As Kelly and Erin stared into one another's eyes, she practically forgot to breathe as it felt like his blue eyes looked straight through to her soul. Her mind raced a mile a minute as she tried to think of something to say to break through the pull that was building between the two of them. Kelly opened his mouth to speak but he seemed to have trouble conveying his thoughts into words.

Erin wished she could just close her eyes and dance to the music, but his piercing gaze had an effect on her that she couldn't even begin to describe. She knew that she was weak when it came to Kelly Severide and that she should not be feeling this way. Jay was at her apartment and he trusted her. Nothing was to happen in this situation. She was resolute about that one.

She pulled away from him and left the dance floor, forgetting her wrap and clutch, simply desperate to get some air. She had just made it outside the hotel when Kelly caught up to her, her belongings in hand.

"What the hell just happened?" he questioned as she took back her clutch.

She shook her head, not even sure that she could put her thoughts into word. But she knew that she owed him an explanation so she tried anyway.

"Kelly, this...you and me, it can't happen. I'm happy to help with the case but I'm with Jay. Any attraction that I still feel for you can't be acted upon."

Erin could swear that the sparkle in his blue eyes dimmed a bit at her words. But he recovered quickly and pasted on his trademark Severide smile.

"I know that," he told her. "We're friends."

A gust of wind blew through the valet entrance of the hotel and Erin shivered, the bare skin of her arms exposed to the elements. Kelly quickly shrugged off his tuxedo jacket and wrapped it around her shoulders.

But as Kelly went on to hand the valet the claim ticket to retrieve his car and get the two of them home, the look in his eyes told Erin that he did not completely accept the friend mandate.

* * *

She dropped her keys onto the table by her apartment door and locked up behind her. Moving further into her place, she found Jay asleep on the couch a case file open on his chest and two empty beers on the coffee table.

"Jay," she whispered gently and kissed him softly which caused her boyfriend to rouse from sleep. She took a delicate seat on the edge of the coffee table and removed her heels for the final time that night.

"You're home," he stated and stretched. "How was it?"

Erin couldn't lie. "I'm glad I was there with them. Seeing Casey accept the award for heroism is just what they've been in need of after these four arsons."

"I trust Severide was a gentleman?"

Her mouth went dry at Jay's question. Truthfully, yes, Kelly had been a gentleman. There had been no true acts of romance between the two of them. But the tension remained. It had cocooned the two of them the entire ride home and if it hadn't been for the sound of The Eagles playing over the radio, Erin could have been strangled by it.

"Of course," she answered easily. She didn't want to focus on Kelly anymore. Her head and heart had to be in this room with the man in front of her. "Let's get to bed. Shift tomorrow."

Tugging on his hand, Erin led him into her bedroom. She hoped that sleep would come easy.

* * *

Erin stayed away from Kelly for a few days, hoping that a cooling off period would let her keep the clear head that she dictated to him before leaving the benefit the other night. But Jay's second look over the case files had actually proven worthy as he had found an interesting fact. The families that had perished in the first three fires had been fostering through Waiting Children, LLC. The connection that Erin had needed so that they could dig deeper had finally revealed itself.

She now had to go check on the little girl from the last fire as well as speak with the girl's father to see if they were also connected to the fostering agency. But rather than bring her partner along for the trip, she wanted Kelly to go with her. Alec Willhite had been giving her daily updates about Korinne and it seemed as if the girl was finally out of the woods. Erin knew that it would be good for Kelly to see the small sliver of good that still existed after these fires.

Erin pulled up in front of the firehouse and killed the engine to her car. She blew out a huge breath before shoving open her door and heading inside. She knew that she needed the chief's permission to pull Kelly off shift and she intended to get that first before she even attempted to find the squad lieutenant.

Connie looked up from her desk as Erin walked into the administrative area and sent her a small smile.

"Chief Boden free for a minute?" she asked and Connie sent her straight inside. Erin thanked the chief's assistant before going to the office and rapping her knuckles on the doorframe. The chief looked up the paperwork that he was completing and waved her in.

"Detective Lindsay, I'm assuming this is not a social call."

"Not completely. I was looking to pull Severide for about an hour. I have to go up to Chicago Med to speak with the vic from the last fire and I'd like him to go with me. She's on the pediatric burn unit but she's awake and alert, healing slowly. I'd like to find out anything that she remembers from the fire."

The chief listened to her request and nodded, knowing exactly her intent behind requesting the squad lieutenant's presence on the hospital visit.

"Go ahead. Just have him take a radio."

Erin nodded and went to go find Severide. It wasn't difficult to do so as he was sitting at the table that had been christened by squad years ago, engaged in a game of cards with Tony, Capp and Rice. Her hazel eyes connected with his blue ones and she couldn't help but smile as he folded his hand and stood up to greet her.

"Boden said you could take a ride. Grab your radio."

He didn't need any further convincing or information. Instead he grabbed his radio and followed her out of the firehouse.

* * *

With a flash of her badge, the nurse manager on the pediatric burn unit led Erin and Kelly to Korinne's room. Her father sat by her bedside and had just said something to make his daughter smile. The left side of her body was dressed gingerly in bandages while her room was littered with get-well balloons and flowers.

"Mr. Sikes, I'm Detective Lindsay and this is Lieutenant Severide. We both responded to the fire the other night. We'd like to speak with your daughter."

The older man nodded and Erin took a seat on the opposite side of Korinne's hospital bed and smiled at the young girl. The young girl looked at her with wide eyes and Erin smiled at her, hoping to put her at ease.

"Korinne, my name is Erin. I'm trying to catch the man that hurt you. Do you think you can answer a few questions?"

"Okay," she answered quietly.

"Your dad said that you were home with your babysitter. Were you awake when the man came into the house?"

"I heard noise so I got out of bed because Ingrid was already asleep so I didn't know if my dad was home. I got down a few of the basement stairs when I saw the man coming in the window. I tried to run but he didn't let me. He pulled me upstairs by my hair," the little girl said and started to cry, obviously remembering the traumatic incident, "He made me lie on the living room as he started the fire, told me not to move or he'd slit my throat."

Erin placed a gentle hand on her good leg, hoping to remind the girl that the horrifying incident she had experienced was over. The little girl panted slightly before she continued.

"I did what he said then I heard Ingrid scream. It got so hot and it hurt my skin so bad. The next thing I remember is waking up here."

"Do you remember what the man looked like? Was he tall like my friend or shorter like me?"

"In between?" Korinne said, a little unsure.

"Was he old or young?"

"Young like you."

"Could you see his hair color?"

"Blonde but it was poking out of hat like yours."

"What about his eyes?"

"They were black."

Erin nodded knowing that the suspect's eyes were most likely not black but she wasn't going to refute the girl's information. She had already given Erin a great deal of information that had not already existed.

"Korinne, you were so brave," Erin told her sincerely. "And you are going to get better with the people in this place because I know a lot of them and they know you are a VIP. We're going to talk to your dad for a minute."

Korinne nodded and hugged her stuffed bear with her good arm. Erin encouraged her father to step out of the room.

"Sir, we're going to put a protective detail outside of Korinne's room. This guy is volatile and we don't know what his next move is." The gentleman nodded his understand. "You said you were a business dinner when we pulled up to the scene. What do you do?"

"I'm a lawyer. We were out with some clients."

"You've been with the firm long? We're just trying to find a pattern between the other victims and your family."

"No, not too long, a little under two years. I was a judge for 15 years before that. Korinne's mom passed away from ovarian cancer, which is when I gave up the judgeship. We adopted her when she was two."

Erin frowned. If Korinne was adopted that meant that there was no connection between this family and the fostering agency.

"Any enemies that you can think of from your time as a judge?"

"None that come to mind. I was in family court so it was a little bit more low stakes than some of my former colleagues."

Erin nodded, the gears in her mind turning. Done with her questions, she thanked Korinne's father for his time and she signaled to Kelly that it was time to go. The detective and squad lieutenant went to the exit of the burn unit and down to the main lobby of the hospital.

"You're awfully quiet," Erin noted as they got to her car.

"Just hard to see her in that state. She's only nine."

"Makes me want to catch this fucker even more. For Korinne and the others."

"Same," he said focusing his eyes straight ahead.

She drove him back to the firehouse and pulled onto the apron to let him out.

"It's just about lunch time. You want to come in and eat?"

The sound of her stomach rumbling at his question was clearly her answer, causing the two of them to laugh. She pulled the car out of the way and the two of them got out, heading into the warmth of the firehouse. Everyone looked up at the guest when she entered with Severide.

"Erin's going to stay for lunch."

It was Sylvie's shift on meal duty, much to the blonde's chagrin. But Erin couldn't deny the wonderful smells that were coming from the small kitchen.

"You putting Rachael Ray to shame back there?" Erin asked leaning against the metal countertop and watched the girl expertly multitask.

Sylvie clipped the kitchen tongs at her, "Rachael Ray has got nothing on me," she answered before a beaming smile crossed her face.

It didn't get past Erin how comfortable she was at 51. From the night she had first stepped through the doors to deal with Vince Keeler's threats, they had treated her with nothing but warmth and kindness. The former was something that was often lacking in police business unless there was a child involved. Boden walked into the kitchen and saw Erin. She stood up straight as the station's leader approached her.

"How did the visit at the hospital go?" he asked

"Korinne had some great intel. I put a protective detail on her room in case our friend tries to tie up any loose ends. It's not his style but I want to be extra careful."

"Are you? Being careful that is. These…arsonists are volatile creatures. If he gets wind that you're closing in on him…"

Erin knew that Boden was brought back to Leslie Shay. It had only been two years since she had been gone and it was still so fresh for everyone.

"I'm being careful chief. There's no official case file that Commander Fisher is aware of so there's no paper trail."

Boden nodded and handed her a plate as Sylvie indicated that the French dip sandwiches and tomato soup was ready. She took a seat near the end of the long wooden table and wasn't shocked when Kelly sat down next to her."

Anybody looking on at the two of them would simply say that they were friends but Erin knew that their relationship was different since the benefit. Despite the cooling off period, Erin felt a strain that had never previously existed between the two of them. She absolutely despised its existence.

Her phone rang before she could give the situation any more thought which was probably best for her sanity. Answering the call, she listened as Mouse told her that crime scene had sent over some information from the fire at the Sikes home. He was going to start running the information against what Jay had discovered the other night. She hung up and Kelly looked at her expectantly. She knew that her tone of voice had indicated that the call had been case related.

"That was Mouse. He heard from the crime scene team."

"What'd they say? Did they find something?" Kelly asked her.

"They found a partial print at the scene."

Erin knew that they would finally be able to develop a list of suspects. Justice was finally within reach.


End file.
